Princess Negotiation (交渉王女, Koushou Oujo) is the fifth chapter in Princess Resurrection manga series.
Hime, Hiro, Riza, and Flandre all take a trip to Hime's summer home. Though Riza had intended to only stop by the mansion to grab her helmet, she ended up unintentionally coming along with them. Angry that she became involved with them again, Riza vents at Hime, who tells her to leave her alone and go to the lake.
While Riza drags Hiro jet-skiing, a lake monster and Hime have a discussion. He regretfully tells Hime that their "deal is off" and that she should flee as soon as possible. Hime only smiles and says that she'll stay a bit longer because she enjoys the atmosphere. When Riza returns, she remarks that she's able to smell beasts, and the house begins to sink into the lake, its foundations snapped.
Hime orders Hiro to hold onto Flandre, as she weighs several tons and will not be able to be rescued if she sinks to the bottom of the lake, but they crash through the floor regardless. Hime and Riza try to escape on a peddle boat, but the monsters catch up to them on shore, and they are captured.
The elder lake monster confronts Hime as she is tied to a pole over a bonfire. The lake monsters wish to drink Hime's blood in order to become immortal, but are unaware that they must die first for it to work. Unwilling to kill any of their numbers for the process, the lake monsters admit defeat, though a lone monster wishes to maim Hime to obtain her blood. Riza steps in to duel the monster in Hime's place.
The next morning, the remaining lake monsters haul Hiro and Flandre out of the lake. Hiro is, of course, dead. Riza requests to stay with Hime longer in order to find out who gave the order for her brother to attack Hime, in order to get her revenge.